2-propyl heptanol alkoxylates and process of cleaning hard surfaces therewith

ABSTRACT

An ethoxylate and a process of cleaning a hard surface with a low foaming detergent includes providing a low foaming detergent composed of the ethoxylate having a general formula which is selected from the group consisting of formula (I): 
     
         C.sub.5 H.sub.11 CH(C.sub.3 H.sub.7)CH.sub.2 O(C.sub.2 H.sub.4 O).sub.n H 
    
     and formula (II): 
     
         C.sub.5 H.sub.11 CH(C.sub.3 H.sub.7)CH.sub.2 O(C.sub.2 H.sub.4 O).sub.p 
    
      (B) r  H, 
     wherein n is 2-16, p is 1-10, r is 1-6, and B is an alkyleneoxy group having 3-4 carbon atoms; and cleaning the hard surface with the low foaming detergent.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to the use of an alkoxylate of 2-propylheptanol in compositions for cleaning hard surfaces. The alkoxylateshows low foaming compared with similar compounds having a hydrophobicgroup of the same size. The alkoxylate may advantageously be used as asurface-active component in detergent compositions.

2. Description of the Related Art

It has long been known to alkoxylate alcohols for obtaining non-ionicsurface-active compounds. These compounds have been used e.g. indetergent compositions because of their wetting and dispersingproperties. In a number of applications, alkoxylates of C₈₋₁₁ alcoholshave however been found to be too high-foaming and/or not to have thedesired detergent power. For example, ethoxylates based on branched C₈alcohols often exhibit acceptable foaming but too low a detergent power,whereas ethoxylates based on straight or branched alcohols having alarger hydrocarbon chain often show an acceptable surface activity buttoo high foaming. Thus, there is a need for new alkylene oxide adductswith an improved ratio of foaming to detergent power.

SUMMARY OF THE INVENTION

It has now been found alkoxylate based on 2-propyl heptanol is suitablefor use as a detergent in compositions for cleaning hard surfaces, sinceit has good detergent and wetting properties as well as low foaming ascompared with other alcohols having substantially the same chain length.In formulations, the alkoxylate also has a desirable thickening effect.In addition, it has been found that the alkoxylate is easily degradableand has a surprisingly low biotoxicity. In tests, no skin-irritanteffect has been noted.

The alkoxylate for use according to the invention can be illustrated bythe formula

    C.sub.5 H.sub.11 CH(C.sub.3 H.sub.7)CH.sub.2 O (A).sub.n H (I)

wherein A is an alkyleneoxy group having 2-4 carbon atoms and n is 2-16,preferably 3-12. Preferably, 50-100% of all alkyleneoxy groups areethyleneoxy groups. In those cases where different alkyleneoxy groupsare present in the same compound, they may be added randomly or inblock.

Generally, the alkoxylate is an ethoxylate having 3-7, preferably 4-6ethyleneoxy groups.

In an advantageous mode of execution, ethylene oxide can be added in afirst step and thereafter alkylene oxide having 3-4 carbon atoms. Thesecompounds can be illustrated by the formula

    C.sub.5 H.sub.11 CH(C.sub.3 H.sub.7)CH.sub.2 O(C.sub.2 H.sub.4 O).sub.p (B).sub.r H                                               (II)

wherein B is an alkyleneoxy group having 3-4 carbon atoms, p is 1-10 andr is 1-6. Preferably, p is 2-8 and r is 1-4. These compounds have lowerfoaming than the corresponding compounds without any alkyleneoxy groupshaving 3-4 carbon atoms.

The alkoxylates for use according to the invention described above canbe prepared by adding in a conventional manner in the presence of aconventional alkali catalyst, such as potassium hydroxide or sodiumhydroxide, the above-mentioned amounts of alkylene oxide to 2-propylheptanol, which is a so-called Guebert alcohol. According to a preferredmode of execution, the addition of ethylene oxide is performed using aconventional catalyst which gives a narrower distribution of addedethylene oxide than any alkali catalyst, such as NaOH or KOH. Thusprepared alkoxylates according to the invention have very low foaming.Examples of conventional catalysts giving a narrow distribution of addedalkylene oxide are Ca(OH)₂, Ba(OH)₂, Sr(OH)₂ and hydrotalcite. Thereaction is preferably conducted in the absence of free water to reducethe amount of by-products and usually at a temperature of 70°-180° C.

The alkoxylate, especially ethoxylate and alkoxylate of formula II, issuitably included in compositions for cleaning hard surfaces, e.g. fordegreasing or dishwashing. Especially good results have been obtainedwhen degreasing lacquered or unlacquered metal surfaces. In addition tothe alkoxylate, the compositions may also contain other detergents, suchas anionic surface-active compounds. Examples hereof are alkyl sulphate,alkyl ether sulphate, alkyl benzene sulphonate, α-olefin sulphonate andalkyl glyceryl sulphonate. Also, the compositions may contain solutisingadditives, complexing agents and/or pH-adjusting agents, enzymes, othersurface-active components, bactericides and perfumes. The compositionsare usually aqueous and in the form of emulsions, microemulsions orsolutions.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The invention will be further illustrated by the following Examples.

EXAMPLE 1

Alkoxylates according to the invention are prepared by alkoxylating2-propyl ethanol with the amounts of alkylene oxide appearing from theTable below in the presence of potassium hydroxide or Ca(OH)₂ ascatalyst. The resulting products were analysed and structurallydetermined by gas chromatography and mass spectrometry. The turbiditypoints were measured in water or monobutylether diethylene glycol. Thefollowing results were obtained.

                  TABLE 1                                                         ______________________________________                                                           Mole of                                                                       alkylene         Turbidity                                 Com-               oxide/mole                                                                              Cata-  point                                     pound Alcohol      of alcohol                                                                              lyst   Water BDG                                 ______________________________________                                        1     2-propyl heptanol                                                                          3.0    EO   KOH    --    40                                2     2-propyl heptanol                                                                          5.5    EO   KOH    --    62                                3     2-propyl heptanol                                                                          8.4    EO   KOH    60    73                                4     2-propyl heptanol                                                                          3.0    EO   Ca(OH).sub.2                                                                         --    29                                5     2-propyl heptanol                                                                          5.0    EO   Ca(OH).sub.2                                                                         --    52                                6     2-propyl heptanol                                                                          7.0    EO   Ca(OH).sub.2                                                                         --    61                                A     2-ethyl hexanol                                                                            2      EO   KOH    --    28                                B     2-ethyl hexanol                                                                            5      EO   KOH    42    --                                C     C.sub.9-11 alcohol.sup.2)                                                                  4      EO   KOH    --    62                                D     C.sub.9-11 alcohol.sup.2)                                                                  6      EO   KOH    56    --                                E     C.sub.9-11 alcohol.sup.2)                                                                  8      EO   KOH    78    --                                F     C.sub.11 alcohol.sup.3)                                                                    3      EO   KOH    --    51                                G     C.sub.11 alcohol.sup.3)                                                                    5      EO   KOH    27    --                                H     C.sub.9-11 alcohol.sup.2)                                                                  4      EO   Ca(OH).sub.2                                                                         --    57                                ______________________________________                                         EO = ethylene oxide; PO = propylene oxide,                                    BDG = monobutylether diethylene glycol                                        .sup.1) PO added first                                                        .sup.2) Dobanol 91 from Shell                                                 .sup.3) Dobanol 1 from Shell                                             

EXAMPLE 2

The foaming properties of the alkoxylates reported in the followingTable were measured according to Ross-Miles ASTM D 1173-53. Thefollowing results were obtained.

                  TABLE 2                                                         ______________________________________                                                       Foam height, cm                                                Compound         0 min   5 min                                                ______________________________________                                        2                18      7                                                    4                0       0                                                    5                5       0                                                    6                10      5                                                    A                40      10                                                   B                50      0                                                    C                80      20                                                   D                95      30                                                   E                45      15                                                   H                20      5                                                    ______________________________________                                    

From these results it appears that the compounds according to theinvention have lower foaming than the most closely related referenceproducts. Thus, compound 2 has lower foaming than compounds A, B, C, Dand E, while compounds 4, 5 and 6 have lower foaming than all thereference compounds.

EXAMPLE 3

On a vertically disposed, lacquered iron plate, smeared with mineraloils, soot, salts and clay was applied 20 ml of a detergent compositionmade up of the following components.

    ______________________________________                                        Parts by weight                                                                              Component                                                      ______________________________________                                        34             Compound 6 or H                                                67             NTA                                                            27             Ethoxylated quaternary fatty amine                             20,000         Water                                                          ______________________________________                                    

The effect achieved was evaluated both with respect to the area of thecleaned surface (i.e. wettability) and with respect to the cleanness ofthe cleaned surface. Cleanness was evaluated according to an ascendingscale of 1-10, where 1 indicates that no improvement of the cleannesscould be observed and 10 indicates a completely clean surface. Thefollowing results were obtained.

                  TABLE 3                                                         ______________________________________                                        Compound      Cleaned surface, cm                                                                        Cleanness                                          ______________________________________                                        6             95           9                                                  H             54           8                                                  ______________________________________                                    

From these results it appears that the formulation containing thecompound according to the invention yielded both improved cleanness anda larger cleaned area.

EXAMPLE 4

The microtoxicity, which is a measure of the aquatic toxicity, wasdetermined for the compounds below as the water concentration of thecompounds at which the ability of luminescent bacteria to emit light for5 min is reduced by 50%. The following results were obtained.

                  TABLE 4                                                         ______________________________________                                        Compound     Concentrate, ppm                                                 ______________________________________                                        2            42                                                               5            31                                                               C            2                                                                D            3                                                                F            1                                                                G            2                                                                ______________________________________                                    

From these results it appears that the compounds according to theinvention have essentially lower microtoxicity than the referencecompounds.

What is claimed is:
 1. A process of cleaning a hard surface with a low foaming detergent, comprising:a. providing a low foaming detergent comprised of an alkoxylate having a general formula which is selected from the group consisting of formula (I):

    C.sub.5 H.sub.11 CH(C.sub.3 H.sub.7)CH.sub.2 O(C.sub.2 H.sub.4 O).sub.n H

and formula (II):

    C.sub.5 H.sub.11 CH(C.sub.3 H.sub.7)CH.sub.2 O(C.sub.2 H.sub.4 O).sub.p (B).sub.r H,

wherein n is 2-16, p is 1-10, r is 1-6, and B is an alkyleneoxy group having 3-4 carbon atoms; and b. cleaning the hard surface with the low foaming detergent.
 2. The process as defined in claim 1, where n is 3-12.
 3. The process as defined in claim 1, where n is 3-7.
 4. The process as defined in claim 1, where p is 2-8 and r is 1-4.
 5. The process as defined in claim 1, wherein groups --(C₂ H₄ O)_(n--) and --(C₂ H₄ O)_(p) -- in formulae I and II, respectively, are provided by ethoxylating in the presence of an ethoxylation catalyst whereby a distribution range for the alkoxylate is obtained which is narrower than that obtained with NaOH or KOH.
 6. The process as defined in claim 1, wherein the hard surface is selected from the group consisting of an unlacquered metal surface and a lacquered metal surface, and wherein cleaning degreases the hard surface.
 7. An alkoxylate having a formula:

    C.sub.5 H.sub.11 CH(C.sub.3 H.sub.7)CH.sub.2 O(C.sub.2 H.sub.4 O).sub.p (B).sub.r H

wherein B is an alkyleneoxy group having 3-4 carbon atoms, p is 1-10, and r is 1-6.
 8. The alkoxylate as defined in claim 7, wherein p is 2-8.
 9. The alkoxylate as defined in claim 8, where r is 1-4.
 10. The alkoxylate as defined in claim 7, where r is 1-4.
 11. The alkoxylate defined in claim 7, provided by a process comprising ethoxylation in the presence of an ethoxylation catalyst whereby a distribution range for the alkoxylate is obtained which is narrower than that obtained with NaOH or KOH. 